Tubing machine



July l, 1930. v J, w DEvlNE 1,768,671

Filed Sept. l, 1927 2 Sheets-Sheet 2 W BY \ Q; Il', l ATTORNEYS Patented JulyV l, 1930 UNITED STATES PATENT OFFICE Y JAMES W. DEVINE, F NEW BRUNSWICK, NEW JERSEY, ASSIGNOR T0 BOYLE, OF PATERSON, NEW JERSEY VERNON TUBING- MACHINE Application led September 1, 1927. Serial No. 216,929.

VThis invention relates to improvements in tubing machines and, more particularly, to the construction of the discharge portion of .such machines.

It has for an object to provide a core and die structure whereby the ow of the material being extruded is regulated so as to promote the quality and uniformity of the product, and whereby the separations occasioned by the spokes of the core bridge are healed and obliterated, so as to eliminate weaknesses or imperfections in the product resulting therefrom.

Another object consists in providing c ertain improvements in the form, construction and arrangement of the several parts, whereby the above named and other objects may effectively be attained. D

Practical embodiments of the invention are represented in the drawings in which Fig. 1 represents a longitudinal section through the discharge portion of a tubing machine embodying my invention;

Fig. 2 represents a detail section taken in the plane of the line II-II of Fig. 1 look-l ing in the direction of the arrows;

Fig. 3 represents a view similar to Fig. 1 but showing a modified form; and I Fig. 4 represents a detail section taken in the plane of the line IV--IV of Fig. 3 looking in the direction of the arrows.

Referring to the form shown in Figs 1 and 2, the front member of the tubing machine head is denoted by 1, and it has the usual channels 2 for permitting the c irculation of a temperature controlling medium, as is well understood in the art.

The said front member is formed with a bore 3 in which the screw or'plodder (not shown) operates in the usual manner.

The said bore 3 is reduced in diameter, as indicated at 4, and it is, forward of this reduced portion, enlarged so as to provide a shoulder 5 against which the core bridge is seated, as clearly shown in Fig. 1.

The said core bridge includes a peripheral member 0f rim 6, a central member or hub 7, and radially disposed spokes 8, connecting the'riin and hub. .l

The hub 7 is bored and threaded, as indicated at 9, so as to receive the threaded end of a clore 10 for removably securing the latter in the hub and thereby causing the core to be supported in position by the core bridge.

The cord 10 has an intermediate portion 11 which is enlarged in diameter, and its forward endis reduced in diameter, as indicated at 12, which reduced end slidingly receives a cone shaped inner die member 13 that has a recess 14 formed therein of such size and shape as to slidably iit the enlarged intermediate portion 11 of the core.

The reduced, end 12 of the vcore is threaded and mates with a nut 15 for adjusting the die member 13 on the core.

The hub 7 is also bored and threaded at its Irear end, as indicated at 16, so as to receive the threaded stem of a tapered extension 17 that is thus supported by the core bridge and projects rearwardly into the reduced p0rtion 4 'of the bore in the front member 1 of the machine.

'Fhe core bridge and core are firmly held in position in the tubing machine by an element 18 that is threaded into the front member 1, as indicated at 19, and abuts the outer face of the rim 6 of the core bridge;

The outer portion of the die includes a part 20 that has a flange 21.formed thereon and faced to abut the shoulder 22 on the element 18. A. ring nut 23, which is threaded into the element 18, holds the part 20 of the die in place.

The bore of the part 20 is shouldered, asindicated at 24, to receive, with a tight lit, a ring 25 that forms theportion of the outer die memberwhich immediately cooperates with the inner die member 13. It will be clear that the said elements 13 and 25 are normally held in their most forward position by the movement of the material being extruded.

Set screws 26 are threaded into the element 18, in radial disposition, and abut the flange 21 on the part 2() so as to provide means for exactly centering the latter with respect to the element 18 and to the core and the inner die member 13. y

The bore of the element 18 is enlarged at 27, and further enlarged at 28, so as to re-' 100 ceive an annulus 29 which has its exterior correspondingly shaped. The inner circumference of the annulus 29 is flared towards its front and rear edges, when viewed in longitudinal section, so as to constitute oppositely lying faces one`of which is longer than the other, as clearly shown in Fig. 1. It is scalloped or corru ated, when viewed in cross section, as will seen by reference to Fig. 2.

Mounted on the core 10, with its ends abutting the hub 7 of the bridge and the enlarged intermediate portion 11 of the core, is a bulging sleeve 30. This sleeve is tapered toward its opposite ends, when regarded in longitudinal section, in a manner analogous to the flare on the annulus 29, but the tapered portions on the sleeve are somewhat longer than the corresponding arts on the annulus. In crosssection, the s eeve 30 is corrugated in substantially the same form as the annulus 29, as will be seen by reference to Fig. 2; and examination of the last named figure will also demonstrate that the annulus 29 and sleeve 30 are complementarily disposed so as to leave a narrow sinuous channel between their most closely adjacent portions. The said channel, of course, increases in Widthboth forwardly and rearwardly of the said most closely adjacent parts of these two elements.

Forwardly of the annulus 29, the bore of the outer die part 20 `expands in diameter slightly and then gradually contracts until it merges into a cylindrical portion 31 at the mouth of the die. This cylindrical portion coacts with a taper portion 32 on the inner die member 13, so that the longitudinal acl-- justment of the latter on the reduced portion 12 of the core, by means of the nut 15, will vary the width of the opening between the inner die member 13 and the ring 25, and thereby determine the thickness of the product extruded from the machine.

A port 33 is formed in the front member 1 of the machine head, and it communicates with an annular groove 34 formed in the rim 6 of the core bridge, which groove opens into ducts 35 in the spokes 8 of the said bridge."

The said ducts debouch into the hollow hub 7 andY the latter communicates with an axial channel 36 formed in the core 10. The arrangement just described enables the introduction of some non-adhesive powder, such as talc, into the interior of the product being extruded, the said powder being forced into the port 33 and being ejected from the forward end of the core 10 into the interior of the tube asy formed.

A suitable heating unit, preferably an electrical one, denoted by 37, may be seated upon the exterior of the outer die part 20 in order to maintain that part of the machine at a proper temperature for the extruding operation.

The form shown in Figs. 3 and 4 is the same as the form shown in Figs. 1 and 2,

except that the core 10 does not have a relatively enlarged intermediate portion corresponding to the portion 11 in Figs. 1 and 2; and the bulging sleeve 30 is omitted.

In operation, the material to be extruded, generally a rubber compound, is urged forwardly from the machine head b'y the usual screw or plodder. It. first encounters the tapering extension 17 which latter opens the material mass centrally so as to facilitate its passage around the hub 7 of the core bridge and the core. The force of the screw squeezes the material through the o enings between the spokes 8 of the core bri ge and the latter, of course, separate the mass into streams or ribbons of material which must be brought together so as to constitute an annular formation as extruded from the machine. The shape of'the space between the annulus 29 and bulging sleeve 30 is so formed as to cause a resistance to the flow of the material as it passes from the core bridge toward the said parts because the space becomes more constricted as it approaches the most closely adjacent portions of the annulus and sleeve; while, at the same time, opportunity is provided'for lateral or circular expansion of the mass of material by reason of the sinuous or corrugated shape of the space between the annulus and sleeve. This sinuous form establishes, naturally, greater circumferential length than would a true circle. The combination of this resistance to longitudinal or forward movement of the mass at this juncture and facilitation of lateral or circumferential movement of the material, promotes a healing or welding of the lines of separation occasioned by the spokes of the core bridge so that, by the time the material passes the most closely adjacent portions of the annulus 29 and sleeve 30 it is substantially homogeneous throughout its corrugated tubular formation.

As the material passes beyond the most closely adjacent portions of the annulus 29 and sleeve 30, opportunity is provided for lateral expansion so that the mass will be substantially circular in cross section by the time it reaches the widest portion of the bore in the outer die part 20. The tapering shape of the ring 25, cooperating with the conical shape of the inner die member 13 again establishes resistance to the forward movement of the material and closely compacts it so that, when it finally passes out or is extruded between the surfaces 31 and 32 of the ring 25 and inner die member 13, respectively, a substantially perfect tubular structure is formed.

It will be observed that the circumferential length of the sinuous openin between the most closely adjacent portions o the annulus 29 and sleeve 30 is substantially the same as the circumferential length of the widest portion of the bore of. the outer die part 20, so

that there is no lateral strain u'oonI the outer surfaceof the material after it leaves the elements 29 and 30, and the forwardly tapering bore within the outer die member has the effect of compacting the outer circumference of the material which is already in good conpoint of location of the annulus 29 is less Severe.

It will be understood that various changes may be resorted to in the form, construction, and arrangement of the several parts, without departing from the spirit and scope of my invention; hence, I do not intend to be limited to the details herein shown andA described except as they may' be included in the claims.

What I claim is:

1. In a tubing machine, a core having a portion which is corrugated in cross-section versely corrugated portion and a circular tapering portion, the corrugated portion being intermediate the other said ortions and the corrugated ortion having aces flaring oppositely in ongitudinal section.

9. A tubing machine head having a bore provided with a cylindrical portion, a transversely corrugated portion and a circular tapering portion, the corru ated portion being intermediate the other sa1d portions and the corrugated portion having faces flaring oppositely in longitudinal section, one of sald faces being longer than the other.

In testimony, that I claim the foregoing as my invention, I have signed my name this 29th day of August, 1927.

JAMES W. DEVINE.

and oppositely tapered in longitudinal section.

2. In a tubing machine, a core havln a portion which is corrugated 1n cross-sectlon and oppositely tapered in longitudinal section and another portion adjacent thereto and in alinement therewith which is circular in cross-section.

3. In a tubing machine, a core having a portion which is corrugated in cross-section and tapered in longitudinal section, another portion which is circular in cross-section, and a third portion which is circular in crosssection and conical in longitudinal section.

4. In a tubing machine, a core and a sur` rounding die member, complementary portions of said core and die member being transversely corrugated and longitudinally tapered and flared, respective y, in opposite directions.

5. In a tubing machine, a core and a sur- `rounding die member, complementary porp provided with a cylindrical portion, a transversely corrugated portion and a circular tapering portion.

7 A tubing machine head having a bore provided with a c llindrical portion, a transversely corrugate portion and a circular ta pering portion, the corrugated portion being intermediate the other sald portions.

8. A tubing machine head having a bore provided with a cylindrical portion, a trans- 

